The default setting for new MK IV SE is jumper set covering pins 1 and 2 (same as unjumpered) for stock M8100/CV4010 tubes. Look at this site and at the bottom the link to the latest reference guide for your amp.

Well I just bought the MKIV from David via his eBay store. Really excited now and can't wait for it to arrive.

I currently have a Fiio E7/E9 setup using Fischer Audio FA-003 headphones. As my budget is limited I also got a Fiio L7 so that I could use my E7 with the USB out from my laptop. Hoping everything sounds ok. I really don't have a clue about tubes.

So i have just taken the plunge into Audiofileism! My first real set up is on its way which consists of Little Dot mk iv se, Little Dot DAC-1, Sennheiser Hd650's and a full compliment of Audioquest cables. Got my PC set up with 320k music through Foobar2000 using asio4all and will be using my SPDIF port when the new system turns up. Only downer is my new lappy that i have all this set up on is playing up and getting sent back first thing Monday for an unknown time period. All my great gear is going to turn up and ill have no source to use it from. But dam im excited!!!

Yo guys I've had my LD amp for about half a year now and for a while I have felt that it was a little bit muddy with my HD650, but now it's all changed.

I just got my 6ZH1P-EV and replaced the stock jan 5654's and all I can say is freaken WOW. The changes are amazing even when not burned in at all. The clarity is amazing, gone are the muddies from the mids. The bass is more tamed now and not as loose as it was before. the highs are crisp and less sibliant as before. soundstage is wider but still shallow given the nature of the HD650's. The vocals are less forward then before and sounds quite good. overall a massive improvement from the stock tubes and this is the impression i get from listening to it for 10 mins. i can't wait when i get about 30+ hours of use on them.

Just wanted to share this. I recommend people to give these a try. I think it might be the most worthwhile 24bucks i've ever spent on audio equiment.

Excellent! I will give those tubes a try. I'm still waiting for my HD650's ATM but have the L.D. system set up. Am currently using my Audio-technica ATH-AD700's. I'm crawling out of my skin to listen to this system with the HD650's. Ive also started compiling a FLAC library. Not the biggest FLAC collection ATM but getting there. Audio = <3